All,
Will the new formula of fuel (E85) damage rubber parts of our older fuel systems? I have a newer carb, rubber lines and fuel pump but worry about the rubber fuel bladder in my 78.

I have been told that there is some addative you can use to offset the negative effect of the e85 stuff (assuming there is some).

Anyone know for sure?
Dan

 

If you're really talking about E85 vs, the much more-commonly available E10...yes, there is some potential for harm to the fuel systems of older cars, especially anywhere rubber hoses are involved. ANY 60s-70s era car should have its rubber fuel hoses checked periodically for signs of rot, cracking, etc. Typically any 60's -era car will have two of these;
One from the tank to the frame and another from the frame to the fuel pump. Ethanol (or any other alcohol compound for that matter) will dry out and deteriorate rubber, and can be a huge fire risk in an old Corvette.

Be advised that MOST commonly-available gasoline right now is E10, or 90% gasoline/ 10% ethanol. Others will chime in as well, but I don't believe a carbureted car that is jetted for 'regular' gas will run properly on E85 (85% ethanol/15% gasoline)- with normal jetting it would be way lean and (with a Holley carb, for instance) I'm not sure if a simple rejet would be adequate to make most carburetors run properly with E85- the idle calibrations wouldn't allow for it; again too lean.

 

http://pure-gas.org/

 

As mentioned, E85 needs to jetted much richer, as ethanol only has 65% the energy as gasoline. Lot's of pump gas is 10% ethanol, so hard to avoid sometimes, and not to bad on rubber/plastic parts. When E10 first came out, some stations were cheating, illegally using cheaper methanol(wood alchohol), that really attacks rubber. This was causing damaged carburator parts, and law suites over this. Happened to my car, as the Union 76 station I was using, turned up doing this in an investigation. Didn't sue anyone though.

 

As said DON'T USE E85

 

Without extensive mods, you can't run E85 in your Vette, so don't do it.

Current pump gas is E10, and there is possibility of increasing that to E15. The biggest problem with the ethanol-enhanced E10 is that it will destroy the stock accel pump in a Q-Jet if an ethanol-compatible pump has not been installed. This will cause hard starting and hesitation & engine stalling when pulling out from a standing start.

Lars

 

GM has marketed a number of E85 Flex Fuel vehicles here in Canada for a number of years. They have specially developed components to resist the damaging effects of 85% ethanol. GM has run into one major problem: there are no E85 fuel stations here. That's a major marketing Ooops. We do have the 10% mix.

And with major corn crop failures this summer in the USA and Canada owing to drought I don't see things changing soon.

 

just got back from filling my '69 with 100% gasoline





don't even want e10 in it. it was $3.93 for 93 octaine.

 

I can't find your accelerator pump test post. That was very revealing as to what ethanol does to the rubber cups. Do you still have it?

 

The EPA has mandated that it's going to be 15%. Get ready. They don't care what it costs, it's a "just do it 'cause we said so".

http://www.bikerspost.com/forum/topi...otorcyclists-1

 

It's here:
http://forums.corvetteforum.com/c3-t...t-quality.html

But I have deleted the photos to free up space...

Text of the whole thing here:

A while ago, I posted a thread titled, “Hooker Supercomp Sidemount Headers: Horrendous Product Quality.” From the response to the thread, and from the e-mails I have received, I’m not the only one who is sick and tired of manufacturers producing garbage, selling it to us for inflated prices, and not giving a squat.

The idea of people knowingly selling defective products really gets under my skin, and I hope it does you, too. So let me expose yet another horrible case of a manufacturer knowingly selling defective products that can damage your Vette and potentially kill you: Every Vette owner with a Q-Jet carb needs to be aware of this:

Echlin/NAPA has been selling known defective accelerator pumps in their Q-Jet carb kits for over 2 years now. The pumps contained in the kits are not compatible with modern pump gas. Yes, you read that right: The parts in the carb kit are not compatible with fuel! When the “stock” accel pump in their kit is exposed to current gasoline pump blends, the pump rubber swells, becomes soft, seizes in the pump bore, and shears itself off the pump shaft. This results in a completely inoperative accelerator pump, which will cause your car to stall under sudden acceleration, such as when pulling out into traffic… need I expand more on the situation this can lead to…?

NAPA/Echlin has been aware of this for over 2 years, yet continues to sell defective pumps in their kits. If you want a pump that can be used in gasoline, you have to buy a “special” pump for an additional $20.

Are you kidding me…??

The photos below show the garbage that Echlin/NAPA is selling. The carb in the photos was installed on a ’68 Vette and run on pump gas in Oklahoma with a carb kit and accel pump from NAPA/Echlin. After hours in service, the pump swelled and sheared itself right off the pump shaft. The rubber remained seized in the pump bore while the upper pump rod continued to move up and down as if it were operating normally. The car had a dangerous stumble, and would die on sudden acceleration following installation of the Echlin parts.

I have seen several dozen of these defective Echlin pumps, and Echlin is fully aware of the problem. They flat don’t care. I’m mad. As the owner of a valuable car, you should be mad, too, that these people are selling you this trash:

Here are some photos showing my testing of various accel pumps for those interested in this problem:

My test setup is pretty basic: A bunch of accel pumps, including a brand new Echlin pump (box on far left), a Q-Jet carb with the airhorn removed, and a can full of pump gas to soak the pumps in:

The pumps are soaked in plain ol’ unleaded pump gas for an hour:

The pumps are then inserted into the pump bore in a Q-Jet that has been filled with the same fuel. The stroke of the pump is slowly verified to assure that the pump will travel the full distance of the bore without seizing – most pumps fail the “slow depress” test and lock up in the bore before they hit the bottom of the stroke:

The soft, swollen diaphragms will peel off many of the pump shafts on the spring-induced return stroke:

If the pump passes the “slow stroke” test, it is depressed in a normal manner several times to verify strong and consistent pump shots. Here is a good pump doing its thing, with a solid, violent shot of fuel coming out the discharge passage – every time. A bad pump will produce no pump shot whatsoever:

Here are the pumps that failed the tests. Note the brand new Echlin pump on the far left is part of the “bad” group. The other pumps are random pumps I had in my parts stash:

Close-up of the “bad” pumps show that they are all different styles, including pumps with and without the “skirt spring”, made from different materials as indicated by color. Notice how the new Echlin pump has “flared out” from the fuel swelling: This flare-out causes the pump to lock up in the bore and fail:

And here are the “pass” pumps. Note that two of the pumps are actually old-style pumps with the old black rubber, and one is a “skirt spring” style pump. Note how the blue “skirt spring” pump has not swollen or flared out: It has retained its “tucked in” appearance, even after having been soaked in fuel for several hours:

My suggestion to you if you rebuild your carb:
• Make sure the parts guy you’re buying from is aware of the bad accel pump problem, and that he is willing to exchange the pump with you if the pump in your kit is bad.
• Test the pump before you install it: Soak it in gasoline for several hours, and then test it in your pump bore: Make darned sure it produces a solid shot of fuel with every stroke, and make sure it does not bind, stick, or jam in the bore – it should operate smoothly, with a constant pump shot stream from the top of the stroke to the bottom.
• If it’s bad, take it back and have them give you another pump. Repeat the entire above operation.
Whatever you do, don’t install a bad accel pump in your carb – it’s dangerous to both you and your car…

In addition to the pumps sold by Cliff and Henry, my latest testing shows NAPA/Echlin part number 2-4055 to be a good pump at this time. This pump has the garter spring, the dark blue cup as shown on the photos of Cliff's pumps above, and the better cup retaining feature. I just bought all the ones available in the Rocky Mountain Region but there are more pumps scattered through warehouses across the country. They sell for about $5 each.

Lars

 

I know this thread is a bit old but saw the comment from TimAT about an E15 mandate.

Ugh.

Not only do you have to worry about hoses and seals in your fuel system, but it's also important to note that your carburetor mixture will be off with these changes. If you were running a little rich before, you should be OK. If you were running on the edge of lean, you'll probably be too lean.

The E85 FFV vehicles have sensors that determine the ethanol percentage and scale the fueling requirements based on that. Non E85 vehicles and carbureted cars are completely unaware. A regular EFI car will also run off during open loop operations as they have no way to scale against the different fuel chemistry.

 

As of July 2012 there was a grand total of ONE gas station in all of North America selling E15. By law, this sticker:



must be present on E15 pumps. Given the stern warnings and the fact that most of not all OEMS have condemned E15, it's unlikely that E10 or pure gas is going away soon.

 

Sweet. I hope you're right. The environmentalists haven't proven to be the sharpest sticks in the bunch. (MTBE)

 

[QUOTE=TimAT;1581571346] They don't care what it costs, it's a "just do it 'cause we said so".

[QUOTE]

Besides "saving the earth" reason I believe it is just another way in which those pushing the crap can discourage ownership, collection, etc. of our older cars and getting us into those little fart carts now being manufactured. Are ready to dump your Vette in favor of a Prius, et al?

 

As Lars has stated, be careful with accelerator pump rubber on the Q-jet.

Something I haven't seen discussed, and I just discovered, is Holley now recommends their green rubber accelerator pump diaphragms for all fuels in their carbs. I just ordered their standard one for my tri-power rebuild, and then I began to wonder if that was correct. Upon calling them, they said they include it in their rebuild kits and recommend it for gasoline and 10% alcohol fuels. I asked why they were still selling the other one, got no response.

Only question I have about the new rubber is that it seems exremely stiff (at least the one I got). A lot of effort is required to press the diaphragm through it's working area. Almost thought it would over-ride the pressure on the actuator arm spring. Will have to see how it works.

Something you Holley guys may want to consider.

Ralph.

 

If there is a reliable source of E85 AND it is converted for it, it is VERY high octane. Many guys on speedtalk run 13.5:1 Good power gains!
The big cam guys are over 14:1
But, do your own research before changing heads and pistons! No E85 at my stations.

 

Most pump E85 has an AKI of only 94-96, not that much more than some of the pure gas pumps.